Fossils from the Cambrian era are very important in the overall study of the evolutionary process.
(Mirror Daily, United States) – After determining only last week that the oldest multicellular animal was the sea-sponge that evolved somewhere around 640 million years ago, now scientists uncovered the nervous system of a 520-million-year-old shrimp.
Researchers managed to find the remains of a creature that resembles a sort of armored head shrimp. But the most important part of the discovery is that somehow, the fossil got so well preserved that the nervous system can be easily distinguished and studied.
This discovery bears great significance in the world of science because researchers can now decipher the complex evolution of the nervous systems that belong to the animals that currently populate the planet.
According to the scientists, the remarkably preserved fossil is that of a Chengjiagocaris kunmingensis. The creature was a sort of modern-like crustacean that lived in South China, or at least what we know now as being the southern region of China, roughly 500 million years ago.
The Chengjiagocaris kunmingensis had a long, straight nerve cord that extended throughout the lengths of its body. The scientists also found visible traces of nerve tissue clusters arranged along the central cord. The fossil is so well preserved that the researchers could also distinguish individual structures of nerves.
It seems that the ganglia grew smaller and smaller as it distanced itself from the head of the shrimp. Furthermore, the researchers found that the same ganglia were linked with the crustacean’s legs that were also progressively smaller.
The scientists that studied the incredibly-preserved fossil determined that some of the nerve clusters resembled those found in modern-day worms, but did not appear in arthropods. This is a significant clue regarding the evolution of various life forms that shared a lineage along the millions of years that passed.
The Chengjiagocaris kunmingensis lived in the Cambrian period. This geological era is believed to be the time in which life flourished on our planet. The rapid spread of multicellular organisms that took place at the time is also called the Cambrian explosion.
It is the scientists’ opinion that the Chengjiagocaris kunmingensis belonged to the fuxianhuiids. These were the predecessors of modern day arachnids, crustaceans and insects.
According to the co-author of the study, Javier Ortega-Hernandez, a Cambridge University biologist, the arthropods that belonged to the fuxianhuiid class spend their life on the bottom of the sea feeding with their long front feet.
Ortega-Hernandez said that the largest specimens reached up to 6 inches in lengths, and they had minimum 80 legs.
The field of Evolutionary studies is rapidly developing as scientists uncovered the nervous system of a 520-million-year-old shrimp, proof that multicellular organism existed in the Pre-Cambrian era and that the inhibitory cascade rule is responsible for teeth evolution. And all of this happened in one week.
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